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XElement.Load Method (TextReader, LoadOptions)

Loads an XElement from a TextReader, optionally preserving white space and retaining line information.

Namespace:  System.Xml.Linq
Assembly:  System.Xml.Linq (in System.Xml.Linq.dll)

public static XElement Load(
	TextReader textReader,
	LoadOptions options
)

Parameters

textReader
Type: System.IO.TextReader

A TextReader that will be read for the XElement content.

options
Type: System.Xml.Linq.LoadOptions

A LoadOptions that specifies white space behavior, and whether to load base URI and line information.

Return Value

Type: System.Xml.Linq.XElement
An XElement that contains the XML that was read from the specified TextReader.

If the source XML is indented, setting the PreserveWhitespace flag in options causes the reader to read all white space in the source XML. Nodes of type XText are created for both significant and insignificant white space.

If the source XML is indented, not setting the PreserveWhitespace flag in options causes the reader to ignore all of the insignificant white space in the source XML. The XML tree is created without any text nodes for insignificant white space.

If the source XML is not indented, setting the PreserveWhitespace flag in options has no effect. Significant white space is still preserved, and there are no spans of insignificant white space that could cause the creation of more white space text nodes.

For more information, see Preserving White Space while Loading or Parsing XML and Preserving White Space While Serializing.

Use Parse to create an XElement from a string that contains XML.

Setting SetBaseUri will have no effect when loading from a TextReader.

There is a performance penalty if you set the SetLineInfo flag.

The line information is accurate immediately after loading the XML document. If you modify the XML tree after loading the document, the line information may become meaningless.

LINQ to XML's loading functionality is built upon XmlReader. Therefore, you might catch any exceptions that are thrown by the XmlReader.Create overload methods and the XmlReader methods that read and parse the document.

The following example loads an XElement from a StringReader in two different ways: preserving white space, and not preserving white space. It then uses a query to determine the number of white space nodes in the resulting XML tree.

TextReader sr;
int whiteSpaceNodes;

sr = new StringReader("<Root> <Child> </Child> </Root>");
XElement xmlTree1 = XElement.Load(sr, LoadOptions.None);
sr.Close();
whiteSpaceNodes = xmlTree1
    .DescendantNodesAndSelf()
    .OfType<XText>()
    .Where(tNode => tNode.ToString().Trim().Length == 0)
    .Count();
Console.WriteLine("Count of white space nodes (not preserving whitespace): {0}", whiteSpaceNodes);

sr = new StringReader("<Root> <Child> </Child> </Root>");
XElement xmlTree2 = XElement.Load(sr, LoadOptions.PreserveWhitespace);
sr.Close();
whiteSpaceNodes = xmlTree2
    .DescendantNodesAndSelf()
    .OfType<XText>()
    .Where(tNode => tNode.ToString().Trim().Length == 0)
    .Count();
Console.WriteLine("Count of white space nodes (preserving whitespace): {0}", whiteSpaceNodes);

This example produces the following output:

Count of white space nodes (not preserving whitespace): 0
Count of white space nodes (preserving whitespace): 3

The following example loads the line information as it loads from the TextReader. It then prints the line information.

TextReader sr = new StringReader(
@"<Root>
  <Child>
    <GrandChild1/>
    <GrandChild2/>
  </Child>
</Root>");
XElement po = XElement.Load(sr,
    LoadOptions.SetLineInfo);
Console.WriteLine("{0}{1}{2}",
    "Element Name".PadRight(20),
    "Line".PadRight(5),
    "Position");
Console.WriteLine("{0}{1}{2}",
    "------------".PadRight(20),
    "----".PadRight(5),
    "--------");
foreach (XElement e in po.DescendantsAndSelf())
    Console.WriteLine("{0}{1}{2}",
        ("".PadRight(e.Ancestors().Count() * 2) + e.Name).PadRight(20),
        ((IXmlLineInfo)e).LineNumber.ToString().PadRight(5),
        ((IXmlLineInfo)e).LinePosition);

This example produces the following output:

Element Name        Line Position
------------        ---- --------
Root                1    2
  Child             2    4
    GrandChild1     3    6
    GrandChild2     4    6

Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5

.NET Compact Framework

Supported in: 3.5

XNA Framework

Supported in: 3.0

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